The present invention generally relates to bodily fluid sampling devices and more specifically, but not exclusively, concerns a dispenser for lancet integrated test element units that is configured to minimize the risk of damage of the units prior to use.
The acquisition and testing of bodily fluids is useful for many purposes and continues to grow in importance for use in medical diagnosis and treatment, such as for diabetes, and in other diverse applications. In the medical field, it is desirable for lay operators to perform tests routinely, quickly, and reproducibly outside of a laboratory setting, with rapid results and a readout of the resulting test information. Testing can be performed on various bodily fluids, and for certain applications, is particularly related to the testing of blood and/or interstitial fluid. Performing home-based testing can be difficult for many patients, especially for patients with limited hand dexterity, such as the elderly or diabetics. For example, diabetics can sometimes experience numbness or tingling in their extremities, such as their hands, which can make self-testing difficult because they are unable to accurately position a test strip to collect the blood sample. In addition, wounds for diabetics tend to heal more slowly, and as a result, there is a desire to make incisions less invasive.
Recently, lancet integrated test strips or elements have been developed in which a test strip is integrated with a lancet or other piercing means so as to form a single disposable unit. While these integrated units have somewhat simplified the collection and testing of fluid samples, there are still a number of issues that need to be resolved before a commercial unit can be implemented. One issue concerns maintaining the sterility of the lancet prior to use so as to minimize the risk of infection. Another issue concerns the disposal of used units after use. Once used, the integrated units become a biohazard that need to be disposed of in a safe manner. A number of different types of systems have been proposed for dispensing test strips, lancets, or some combination thereof, but most of these systems have significant drawbacks, especially when used in conjunction with integrated units.
In one typical design, individual test strips are stacked within a cartridge. The test strips are usually dispensed on an individual basis either manually or via a sliding mechanism. Since test strips are dispensed individually, automatic handling of the test strips is rather complicated. The sliding mechanism can jam during dispensing, which can damage the test strips. Usually, after use, the test strips have to be disposed of manually via a separate waste container.
Individual test strips or elements have been formed and/or connected together to form tapes of test strips. In one design, the tape is folded within a case, and individual test elements are manually dispensed by pulling on the tape. However, in the age of smaller fluid sample sizes in which the size of test strips becomes smaller, manual feeding and handling of the tape is not practical due to the size of the test strips involved. Such manual feed designs also fail to provide for automatic feeding of the tape and automatic disposal of used sections of the tape, which are typically needed for modern systems. To address these concerns, automatic feed systems like reel-to-reel cassettes have been developed.
Reel-to-reel type cassettes of test strips, which are similar in construction to normal audio cassettes, address a number of test strip handling and storage issues found with previous test strip cartridge designs. However, it has been recognized that there are still a number of significant drawbacks to reel-to-reel type cassettes, especially for electrochemical test strips, lancet integrated test strips, and other disposables that contain components susceptible to damage. For example, if electrochemical test strips are tightly wound around a reel in the cassette, the electrodes within the test strip can be bent or damaged in such a way to create a short, an open condition, or otherwise damage the electrodes, thereby making the test strip unusable. Similarly, if tightly wound around a reel, lancets within integrated units can be bent or otherwise damaged, which in turn can cause injury to the user or otherwise prevent successful lancing of the skin. To combat this problem, tapes of test strips or integrated units are loosely wound around the reels. However, the loosely wound tape makes the cassettes larger than desired and/or reduces the number of tests available before requiring reloading a new cassette. Even when the tape is initially wrapped in a loose manner, the tape can become tightly wrapped as the tape is indexed, thereby damaging the tape. In addition, reel-to-reel type cassette designs are prone to operating in reverse, which can cause the reintroduction of used test strips into the sterilized supply compartments.
Thus, needs remain for further contributions in this area of technology.